Multiples of four

HOW TO PLAY Four-square is played with a rubber playground ball on a square court with a minimum of four players. When the ball is bounced into a player's square, he must bounce it out without letting it hit the ground twice in his square, or he is out. The object is to eliminate players in higher squares in order to make it to the "four square" and score the most points. Source: www.squarefour.org